An air conditioning unit is charged with a refrigerant. Freon is the term most commonly used for the refrigerant on an A/C system. Freon, or R12, was used until the 1990s but was discontinued because of adverse effects on the environment. The refrigerant now used is called R134a on a vehicle and R22 for a home air conditioning unit.
The Car's A/C Won't Blow Cold Air
A car's air conditioner has both a high and low pressure line. If there is too much refrigerant in the unit, the system may not operate correctly. Have the refrigerant level checked if the air does not come out as cold as it should, usually at least 4.44 degrees C cooler than the ambient temperature.
Rough Idle or Stalling on a Car
The air compressor for the A/C unit may not operate correctly when the system is overfilled with refrigerant. This can actually cause the car itself to run roughly or even die in some cases. A pressure check of the high and low pressure air conditioner lines can determine if too much refrigerant may be causing this problem.
House A/C Unit Doesn't Blow Cold Air
Like a car's air conditioner, a home's air conditioner will also not operate correctly with too much freon. It will operate much like a unit with not enough refrigerant. While the air may still blow from the vents, it will not come out cold enough to efficiently cool your home. Overfilling the system with refrigerant interferes with the operation of the air conditioner's compressor.